The invention relates generally to single lever controls for regulating the throttle and clutch associated with an internal combustion engine. More specifically, the invention relates to single lever controls for marine propulsion devices, such as outboard motors and stern drive units.
Single lever controls generally include a main control lever which is pivotally movable in opposite directions from a neutral position through a clutch operating range to effect clutch operation without affecting the engine throttle setting and subsequently through a throttle control range whereby the engine speed is increased without affecting clutch actuation. As a result, clutch actuation occurs before there is any appreciable advancement of the throttle and the clutch cannot be reversed before the throttle is returned to an idle speed setting.
One general type of single lever control includes means for selectively disconnecting the main control lever from the clutch actuation mechanism when the main control lever is in the neutral position so that the main control lever can be moved independently of the clutch actuation mechanism to advance the throttle setting while the clutch is in the neutral position for engine warm-up. Prior art constructions of this type of single lever controls often include fairly complex mechanisms, particularly those including lockout means for preventing clutch actuation when the throttle is at an advance setting, and usually require lateral movement of the push-pull control cable(s) connecting the control to the remotely located engine clutch and/or throttle. Also, many prior art constructions do not include a positive means for preventing throttle advance during the clutch actuation, but instead rely on the normal backlash in the throttle control cable and throttle linkage to absorb any movement which otherwise would cause throttle advancement.
Examples of prior art single lever controls of this general type are disclosed in the following U.S. Pat. Nos.: Parsons 2,986,044 issued May 30, 1961, Morse et al 3,127,785 issued Apr. 7, 1964, Morse 3,204,732 issued Sept. 7, 1965, Pervier 3,309,938 issued Mar. 21, 1967, Farrington et al 3,842,695 issued Oct. 22, 1964.
Reference is also made to the copending United States Prince Application Ser. No. 767,556, filed on Feb. 10, 1977, U.S. Pat. No. 4,090,558 issued May 23, 1978 and assigned to the assignee of this application.